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  • 1.
    Aasberg, Pål
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Energilager i en överdimensioneradvindkraftspark: En linjäroptimering av batterilager i kombination medintermittenta förnybara energikällor2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A linear optimization has been made to examine the economic viabilityof incorporating battery storage in a wind farm in Sweden. The studyexamines a future wind farm with 10 10 MW turbines. An orographicmapping with height differences and vegetation has been used incombination with measured wind data with IEC-rated anemometersand wind direction sensors between 1997 and 2017 to create asimulated production in the windPRO software. This effect, togetherwith hourly prices from 2021 from Nord pool in SE1, SE2, SE3, SE4and in Estonia, has been used in a linear optimization in Matlab to findthe battery capacity that generates the most revenue. 3 Scenarios areinvestigated where scenario 1 is a wind farm without battery storagewhere all electricity produced is sold directly at the current price.Scenario 2 also lacks battery storage and has a power limit of 75 MWat the transformer whilst the farm still produces 100 MW. Scenario 3has a power limit of 75 MW at the transformer and the possibility ofbattery storage.

  • 2.
    Abdelamir, Zulfaqar
    Karlstad University.
    Fabricability of a high alloy tool steel produced with LPBF, with a focus on part geometry2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Additive manufacturing (AM) is a promising manufacturing process that provides that ability to fabricate components with complex geometries with relatively low lead times compared to other manufacturing processes. This allows for more freedom of design, as prototypes can easily be produced throughout the development process. AM is also especially beneficial in tooling applications, where internal geometries such as cooling channels are required in order to improve the quality of the manufactured parts. These geometries are more difficult to produce with more conventional manufacturing methods such as forging or casting. Currently, Laser Powder Bed Fusion (LPBF) shows the most promise in the field of Additive Manufacturing (AM) of metals, as it offers the freedom to produce complex components with little post processing required. Additionally, post processing with Hot Isostatic Pressing (HIP) can be implemented to significantly enhance the final properties of the material. 

    The LPBF-process can produce many different defects within the parts such as: part porosity and lack of fusion. This is mainly due to the layer-by-layer configuration of the process. Parts can also experience large thermal fluctuations and rapid cooling rates which can generate large residual stresses. This can result in significant cracking in certain high alloyed materials which can impact part quality and  material properties. If the cracking is severe enough, it will result in failure of the entire component and render the entire parts completely useless. Post processing with HIP may remove some of these defects and reduce the residual stresses in the material and thus produce a material with properties that are satisfactory.

    The purpose of this thesis is to investigate the processability of a high alloy cold work tool steel with LPBF. The main focus is the influence of the processing parameters and part geometry on the quality of the produced parts. Furthermore, the influence of the processing parameters on defects and microstructure will also be investigated. The aim is to produce parts that can be enhanced with HIP as a post processing treatment. Additionally, the impact of HIP on the properties of the part will also be investigated in order to determine if the there are any improvements in terms ofreduction in part defects and the removal of any undesired microstructural features which are produced from the process.

    The experimental results showed that the processability of the tool steel is difficult. Several sample volumes were produced with varying processing parameters and scanning strategies, and all the specimens from all sample volumes exhibited some cracking. Parts produced with a combination of contouring and hatching strategy, where there is an internal structure showed the most promise, as these parts exhibited the least amount of severe cracking. However, additional research of the processing parameters and scanning strategies is required in order to reduce the amount of cracking of the external shell structure and thus, achieve proper densification of the parts when post processing with HIP.

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  • 3.
    Abrahamsson, Erika
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Gröna tak - potentialen för dagvattenreglering i Karlstad: Simuleringar i Mike Urban2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As urban areas become more populated and denser, stormwater management becomes an important matter. Since natural areas are becoming exploited and green areas in cities are removed the stormwater flow increases due to the conversion of impermeable surfaces into hard surface areas. The increase in stormwater flow can cause flooding if the pipeline system is insufficient.

    Change in climate caused by anthropogenic emissions will expose our communities to difficult challenges. Urban flooding from sewers is one of them, and may become more frequent in parts of the world where precipitation is predicted to increase in the future. In order to develop our cities in a sustainable manner and create resilience, the urban drainage system has to be a part of this development. Many of the techniques related to sustainable urban drainage systems, like storage reservoirs and open channels, require access to land space. However, about 40-50 % of the impermeable surfaces in cities consist of roof. Consequently, an interesting alternative to decrease stormwater flow is green roof due to its ability to reduce and attenuate the flow.

    The aim of this thesis is to demonstrate the benefits of green roof’s stormwater management through simulations in Mike Urban. The simulations are made over two neighborhoods in Karlstad with future climate changes. The simulations indicated that green roof in these neighborhoods show good potential to lower the risk of flooding and the numbers of flooded wells by a 10- and 2-year rain is decreased by 42 and 58 %.

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  • 4.
    Abrahamsson, Linnéa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Energieffektivisering av fabrik inom tillverkande industri: Utvärdering av åtgärdsförslag2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    June 1st, 2014, the law on energy audits of large enterprises was introduces as a way of promoting energy efficiency and to help fulfil the demands from the EU energy efficiency directive. One company that this law applies to is Talent Plastics in Gothenburg. In 2017 an energy audit was conducted at the company by WSP in Karlstad. This audit has been used as a basis for this study. The purpose of this study has been to present solutions for reducing the energy use as Talent Plastics in Gothenburg.

    In this study, an energy balance for the facility has been modelled. This model has then been used in order to evaluate some of the different solutions presented in the previous energy audit as well as some new solutions that have been identified.

    The solutions that have been studied are:

    Heat recovery from the process cooling by installing a heating battery in

    ventilation systemsHeat recovery from the process cooling by pre-heating ventilation airUpdating old extruder machinesHeat recovery from the compressed air systemUsing outside air for the compressed air systemUpdate of the existing heat recovery system installed in the production

    ventilation system

    Based on the results presented in this report the system today is inefficient with a large need for heat whilst a lot of energy is cooled through process cooling. The energy balance presented showed a higher use of energy for heating of ventilation air compared to the results presented in the previous energy audit. This is a consequence of the assumptions made when conducting an energy audit. By underestimating the energy need for the heating of ventilation air, the potential energy savings from solutions including heat recovery in the ventilation systems has been underestimated.

    Out of the solutions investigated in this study, updating the heat recovery system in the ventilation system for production spaces resulted in the largest energy savings with savings of 192 MWh per year. The maximum energy savings using heat recovery from the process cooling were 202 MWh/year. This solution had a pay-off time of 0,7 years. The results showed that heat recovery from the compressed air system is not a suitable solution for the facility.

    When combining different solutions updating the existing heat recovery system installed in the production ventilation system combined with pre-heating and installation of a heating battery in the same ventilation system would result in energy savings of 323 MWh per year. This represents 14 % of the total energy use for the facility and savings of 226 thousand Swedish krona per year.

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    Energieffektivisering av fabrik inom tillverkande industri
  • 5.
    Adolfsson, Karin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Albinsson, Stina
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Friår - av vilken anledning?: Kopplingar mellan anledningar till friår och livsformerna2007Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Undersökningens syfte är att se vilka anledningar individen har till att välja friår och hur det kopplas samman med livsformerna de lever. Syftet har också varit att se individens upplevelse av friåret och vad de använt friåret till. Undersökningen bygger på kvalitativa intervjuer med sex friårslediga. Intervjuerna har handlat om individens upplevelse av friåret och tiden före det.

    Friår är en arbetsmarknadspolitisk åtgärd med målsättning att ge arbetstagare en längre ledighet från sitt arbete. Arbetslösa får samtidigt en chans att komma in på arbetsmarknaden. Friåret innebär att vara ledig från sitt arbete i tre till tolv månader för att kunna göra något annat utanför arbetsplatsen. För att kunna undersöka av vilka anledningar individen har friår och hur det kopplas med de olika sociala strukturer som villkorar människors vardag. Vi har studerat om livsformsanalysen kan användas till att beskriva, förklara och förstå skillnaderna i människors vardag. Livsformerna är sociala strukturer som villkorar människors vardag. De olika livsformsbegreppen som vi har använt oss av är arbetarlivsformen – husmorslivsformen, karriärenslivsform – representationshustrunslivsform och självständighetens livsform – medhjälperskans livsform. Det är dock vanligt att leva en blandning mellan två eller flera livsformer, det kallas en blandform.

    Vi har kommit fram till att livsformerna till viss del kan kopplas samman med hur intervjupersonerna lever under sitt friår och av vilken anledning de har friår. Det visar sig i att de som använder friåret till att starta ett företag lever till stor del självständighetens livsform. Att använda friåret till utbildning kan kopplas samman med karriärens livsformer. Vidare kan vi se att karriärenslivsform kan kopplas samman med att pressen på arbetet är stor och då är rekreation under friåret vanligt. Många kvinnor lever blandformer och det gör att de har svårt att kombinera de olika arbets- och kärleksformerna. De använder friåret till att ta hand om sin familj och sig själva.

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  • 6.
    Afverberg, Marcus
    Karlstad University.
    Optimering vid byte av fyllningsplatta2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport är en del av ett examensarbete på högskoleprogrammet i maskinteknik vid

    Karlstads Universitet med programkod MSGC17. Arbetet omfattar 22.5 högskolepoäng.

    Arbetet har utförts på Swegon Operations AB i Arvika.

    På fabriken i Arvika tillverkas ljuddämpare för ventilationssystem. I tillverkningscellen där

    dessa ljuddämpare tillverkas sker ett moment där en platta ska bytas mot en annan platta av en

    robot, detta moment fungerar inte optimalt och orsakar stora störningar i produktionen. Dessa

    plattor kallas fyllningsplattor. Varje modell av ljuddämparna har en egen fyllningsplatta. Vid

    tillverkning måste dessa plattor alltså bytas vid byte av storlek av ljuddämpare. Målet med

    projektet är att hitta en lösning på problemet.

    För att nå målet med projektet utfördes arbetet enligt produktutvecklingsprocessen. Utifrån

    förundersökningen som bestod av att samla in data om hur situationen såg ut idag och vad

    som felade skapades en kravspecifikation för den nya lösningen. Koncept skapades i

    idégenereringsprocessen som sedan sållades för att ta fram den bästa lösningen. En

    layoutkonstruktion skapades av konceptet.

    Projektet resulterade i en lösning där alla fyllningsplattor ersattes med en fixerad platta som

    passar alla storlekar av ljuddämparna. Detta genom en fyllningsplatta med slitsade hål som

    fyllningsrören kan förflytta sig i med hjälp av motordrift. Detta medför att roboten helt enkelt

    kan tas bort.

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  • 7.
    Agardson, Agnes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Konceptframtagning av maskinstativ för användning i nyttofordon: Design för möjliggörande av ergonomisk och enkel maskinanvändning2023Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This Bachelor of Science thesis has been carried out during the spring of 2023 as a part of thecourse Degree Project for Bachelor of Science in Innovation and Design Engineering atKarlstad University. The degree project comprises 22,5 credits and the responsible student isAgnes Agardson with Johan Strandberg as supervisor and Leo De Vin as examiner.

    The project is performed in collaboration with the consulting company Rejlers on behalf ofone of their clients. In earlier stages of this cooperation, a machine has been developed andthis project is about further development within that same area. The purpose of this thesiswork is to create a solution on how to implement this machine in a commercial vehicle andadapt it to the user's needs and wishes and then perform a product development process withthe goal of developing a proposal solution that is presented with sketches, a prototype and CAD models.

    The main parts of the process has been divided into phases, a start-up, exploring, define,develop, deliver and a final phase that include a summary of the deliver phase, a writtenthesis, a final presentation and an exhibition. Some elements that were important in thisproject under these headings were, among other things, project plan, feasibility study, problemformulation, requirement specification, idea generation, concept selection, conceptdevelopment and construction.

    The process resulted in a concept proposal of a machine stand that is presented primarily via aCAD model but also with the help of sketches and a simple prototype. This concept proposalsolves the project’s main problem formulation and meets all predetermined requirements. Thesolution involves a foundation made of bent stainless steel sheet that is attached to the floor ofthe cargo compartment of a van. In this foundation, rails can be attached at different heights toadapt to the user’s height and position of the product, in turn a plate is attached to the rails, towhich the machine is attached. A locking function prevents the machine from moving wheninside the car and also allows the solution to be pulled out in several positions, a user modewhere the machine is only pulled out enough to enable use and a so-called service modewhere the machine is pulled out to the maximum to enable maintenance.  

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    Konceptframtagning av maskinstativ för användning i nyttofordon
  • 8.
    Agnelli, Filippo
    et al.
    Ecole Polytech, FRA.
    Constantinescu, Andrei
    Ecole Polytech, FRA.
    Nika, Grigor
    Weierstrass Inst Appl Anal & Stochast, DEU.
    Design and testing of 3D-printed micro-architectured polymer materials exhibiting a negative Poisson’s ratio2020In: Continuum Mechanics and Thermodynamics, ISSN 0935-1175, E-ISSN 1432-0959, Vol. 32, no 2, p. 433-449Article in journal (Refereed)
    Abstract [en]

    This work proposes the complete design cycle for several auxetic materials where the cycle consists of three steps (i) the design of the micro-architecture, (ii) the manufacturing of the material and (iii) the testing of the material. We use topology optimization via a level-set method and asymptotic homogenization to obtain periodic micro-architectured materials with a prescribed effective elasticity tensor and Poisson’s ratio. The space of admissible micro-architectural shapes that carries orthotropic material symmetry allows to attain shapes with an effective Poisson’s ratio below −1−1. Moreover, the specimens were manufactured using a commercial stereolithography Ember printer and are mechanically tested. The observed displacement and strain fields during tensile testing obtained by digital image correlation match the predictions from the finite element simulations and demonstrate the efficiency of the design cycle.

  • 9.
    Agnelli, Filippo
    et al.
    CNRS, École polytechnique, FRA.
    Nika, Grigor
    Weierstrass Institute for Applied Analysis and Stochastics, DEU.
    Constantinescu, Andrei
    CNRS, École polytechnique, FRA.
    Design of thin micro-architectured panels with extension–bending coupling effects using topology optimization2022In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 391, article id 114496Article in journal (Refereed)
    Abstract [en]

    We design the micro-architecture of thin elastic panels to control their macroscopic behavior, accounting simultaneously for in-plane stiffness, out-of-plane stiffness and the extension–bending coupling effects. Our topology optimization method combines inverse homogenization, the Hadamard shape derivative and a level set method in the diffuse interface context to systematically capture within the unit cell the optimal micro-architecture. The efficiency of the solution method is illustrated through four numerical examples where the designed shape yields an important extension–bending coupling. The deformation responses under tensile loading are assessed numerically both on the complete periodic panel and on its homogenized twin plate. The results demonstrate that the simultaneous control of the in-plane, out-of-plane and their coupled behavior enables to shift a flat panel into a dome or a saddle shaped structure. Moreover, the obtained unit cells are elementary blocks to create directly 3D printable objects with shape-morphing capabilities.

  • 10.
    Ahl, Daniel
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Analysis of how different mesh functions influence the result in CFD-simulation of a marine propeller:  2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 11.
    Ahl, Elin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Nordberg, Nina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Planning a digital transformation for a company with a process layout: A study conducted at voestalpine Precision Strip AB2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Digitalization is an upcoming trend that divides the manufacturing industry of today. As an increasing number of companies chose to implement digitalization as a business strategy, some companies still struggle with implementing digitalization into their businesses.

    Previous research has developed digital transformation models, but has been admitted as too generic. This thesis used the most comprehensive transformation model as base and aimed to make it practically implementable for a manufacturing company with a process layout. To enable this, a case study was conducted on a steel-processing company with this layout design. This thesis had an inductive approach, where primary data were collected from one selected company through a pilot study and semi structured interviews, and secondary data were collected through a literature review.

    During the study, it was discovered that a company can benefit from using a customized guidance of how to implement digitalization, to optimally use digital opportunities. This thesis contributed with additional steps and extensions of the previous transformation model. The contribution consisted of the involvement of competency, creation of definition, identified digitalization trends relating to a SWOT analysis, additional phenomenon to take into consideration when analyzing future scenarios, additional questions to consider when analyzing impacted areas, creation of a digital business strategy, a comparison of impacted areas with previous projects, additional identified actions to fill the gap between current state and goals, and five identified criteria’s on how to prioritize these actions. This study extends current research with details and depth regarding a digital transformation model, and hence make it more practical. For future research, a case study testing the potential of the transformation model on a similar company should be conducted, and thereby improve the model further.

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  • 12.
    Ahmad, Muhammad Ovais
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Psychological Safety, Leadership and Non-Technical Debt in Large Scale Agile Software Development2023In: Proceedings of the 18th Conference on Computer Science and Intelligence Systems, FedCSIS 2023, Poland: Institute of Electrical and Electronics Engineers (IEEE), 2023, p. 327-334Conference paper (Refereed)
    Abstract [en]

    Psychological safety has been hypothesised as an important antecedent of the success of agile software development (ASD) teams. However, there is a lack of investigation on psychological safety in large-scale agile (LSA) software development teams. This study explored the antecedents and effects of psychological safety on LSA teams. We conducted semi-structured interviews with software professionals working on LSA project in a Scandinavian technology company. The results suggest that building a psychologically safe environment is a multi-dimensional factor that requires proactive leadership approach, open communication and constructive feedback. The focus should be on designing teams for learning, remuneration safety, and a well-prepared onboarding process for new team members. A psychologically safe environment contributes to effective teamwork, work satisfaction, and promotion of learning. Absence of such an environment leads to brain drain, highlighting the consequences of neglecting this essential aspect of organisational culture. Future research directions are proposed in this paper.

  • 13.
    Ahrnens, Alexander
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Lägesställare med I/P-omvandlare som alternativ2016Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report covers a project instigated by Lennart Proper, Aspervall Instrument AB. The report deals with the development of Aspervalls pneumatic actuator, ASPEdonet and it is a part of the course degree project of Bachelor of Science in Mechanical Engineering, MSGC17. The course covers 22.5 ECTS credits and it was accomplished during the spring term of 2016 at the faculty of health, natureand engineering, Karlstad University. Aspervall is a company located in Säffle that specialize in precision engineering, contract manufacturing and development of own products like ASPEdonet. ASPEdonet is a pneumatic actuator constructed of a pneumatic double-acting cylinder and a positioner. The pneumatic cylinder is used to convert air pressure into mechanical work through the moment of a piston with piston rod in a cylinder tube. The positioner is used to regulate the pressure to different sides of the piston with the use of a control signal. The thesis objective was to further develop the pneumatic positioner by converting it to electropneumatic, which means that the previous pneumatic control signal was replaced with a electronic analog control signal. This was accomplished through installing proportional technology into the positioner in the form of an I/P-transducer. I/P-transducer is also preferred to as E/P-transudcer or proportionalvalve, is a pressure regulator that is used to regulate air pressure proportional to an electronic signal. The problem definition of the project was how the positioner could be complemented with a I/P-transducer without compromising the basic function or the design of the positioner. The project followed the different stages of the product development process, pre-study, product specification, idea generation, concept selection and structure with detail design. The project resulted in a documentation that can serve as basis for product manufacturing and further development. The solution that was generated has the same basic construction and design as the previous model. Norgren VP12 was selected as I/P-transducer since it is compact enough to be integrated in the positioner. Standard components from Norgren and Nelco served as fittings and cable gland. A new more compact valve was designed as a part of the construction, the valve is manufactured from a single unit.

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  • 14.
    Aiki, Toyohiko
    et al.
    Gifu University, Japan.
    Anthonissen, Martijn
    Eindhoven University Technology, Netherlands.
    Muntean, Adrian
    Eindhoven University Technology, Netherlands.
    On a one-dimensional shape-memory alloy model in its fast-temperature- activation limit2012In: Discrete and Continuous Dynamical Systems. Series S, ISSN 1937-1632, E-ISSN 1937-1179, Vol. 5, no 1, p. 15-28Article in journal (Refereed)
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  • 15.
    Aksoy, Can Aksoy
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Fuel consumption measurements and fuelconditioning in high-pressure fuel systemfor single cylinder test cell2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis is part of a bigger project issued by AVL with the purpose to design a high pressure compression ignition fuel system for their single cylinder test cell at their facility in Södertälje. Typically compression-ignition fuel tests are being run within an operating pressure range of 500-2400 bar, but this system has to be able to run with pressures up to 3500 bar. The project was intended to be carried out by two participants where this master thesis covers the evaluation of how fuel consumption rates shall be measured in the system described above as well as how the fuel shall be conditioned.

    The selected concept for measuring fuel consumption rate was based on measuring the mass flow on the low-pressure side of the system with a Coriolis flowmeter. The chosen temperature sensor for monitoring the temperature on the high-pressure side was a K-type thermocouple which would be directly connected to the fuel rail in the system. A bleeder was selected on the basis that it had been used in one of AVL's old test cells. A heat exchanger could not be chosen. However a rough estimation of the capacity needed for a heat exchanger was calculated for future reference.

    The methodology used to develop a concept was based on the engineering project process taught to students at Karlstad University. First a project plan was made followed by a solution-independently expressed product specification including a specification of requirements and QFD-matrix. Several concepts were generated for measuring the fuel consumption by evaluating different measuring principles, available components, possible positions of the components within the system and combinations with different fuel supply concepts. Less extensive methods were used for the remaining tasks in the detailed engineering phase of the project. The concepts were compared using Pugh's analysis and a concept was selected in collaboration with AVL.

    The majority of the objectives for this master thesis could be successfully carried out. The documentation and drawings requested by the client, manufacturing of the system, implementation and validation into the test cell could not be done due to lack of time. This, along with the selection of a heat exchanger and low-pressure thermocouple was left for future work.

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    Arkivfil
  • 16.
    Alexandersson, Jenny
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Förändring av layout och produktionsflöde: Med fokus på förbättringar och struktur i produktionen2018Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This project has been implemented as a degree of Bachelor of Science in Innovation and Design at the Faculty of Health, Science and Technology at the University of Karlstad. The project started in November 2017 and continued to May 2018.

    The most of the work has been performed on the company KD: Solskydd AB in Degerfors. The main task of this project was to develop a new flow-oriented factory layout, to one of the departments in the company. The work included many observations and interviews, it was a big part of the specification and preliminary study. The analysis part of the project was to investigate the possibilities to a better flow in the production and opportunities for improvement in the factory. The methods that were used in this project were establish in Lean.

    From the product development process strategy have a project can be formed and performed. The process has been adapted to this project.

    Ten separate ideas of layouts were made. Each idea fulfilled the specification different. A group of selected co-workers from the compony and some of the persons in the board of the company, got a presentation of the ten ideas. The group discussed the separate ideas from the information they have of the ideas, from that they select one of the layout ideas. To be the one!

    A simulation of the new layout was performed in Karlstad Lean Factory. Nine employees from the company participated in the simulation. The simulation helped the co-workers to see improvements in the production flow.

    In the end of the project investigated the possibilities to more improvement areas in the company, with help from Lean.

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  • 17.
    Alfredsson, Svante
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Konceptutveckling av transportlösning för kaffeutrustning till event2016Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    This thesis is done during the spring semester 2016 for the Bachelor of Science in Innovation and Design programme at Karlstad University. The mission of the thesis was provided by the company 3TEMP AB in Arvika.

    In order to serve large quantities of coffee at big events, festivals and fairs a powerful coffee machine is required. Due to its size the machine is difficult handle during transport. This project is about finding a solution that makes the transport of the coffee machine and its related equipment safer and easier to handle during transportation between events.

    The goal of the project was to find a possible solution that makes the transportation of the equipment more efficient and ergonomic. In order to find as many ideas as possible the design process has been used. This includes a research followed by an ideation, concept development and concept evaluation. The project ended with one concept presented in the form of a layout design in CAD together with assembly drawings, sketches and a model.

    In this project interviews and observations has been done together with the people who transport coffee equipment on a daily basis. The results of the observations were later compared with the recommended lifting weight for manual lifting tasks using NOISH lifting equation. In the event business different types of vehicles are used to transport equipment at the event areas. Everything from ATVs and snowmobiles to tractors and caterpillar vehicles are used. In the project there has been a search for a common denominator between those vehicles.

    During the project benchmarking of similar products has also been done to find inspiration for new ideas. To further evaluate the concepts an examination of laws and regulations for transportation of equipment in traffic and off-road has been done.

    The equipment also has to withstand long distance transport by rail, road, sea and air. To meet these requirements interviews were made with the company MariTerm AB who works with educating in cargo securing of goods for worldwide shipment.

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  • 18.
    Almström, Daniel
    Karlstad University.
    Organizational Misbehaviour: Om olika yrkeskategorier – En jämförande studie2007Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    I denna studie kommer jag att jämföra kollektivanställda och tjänstemän på en större processindustri i Värmland. Syftet med att jämföra de olika grupperna är att se om det skiljer sig mellan handlingar som kan tolkas som organizational misbehaviour.

    Denna studie är utav en kvantitativ karaktär där graden av organizational misbehaviour har undersökts mellan de två yrkesgrupperna med hjälp av enkät. Urvalet omfattar totalt 300 stycken anställda, respondenterna var jämnt fördelade mellan de olika yrkesgrupperna för att göra en så rättvis undersökning som möjligt.

    Jag har valt att mäta Organizational misbehaviour i följande variabler (1) om de anställda använder Internet till privata syften (2) ringer privata samtal på arbetsgivarens telefon (3) gör privata ärenden på betald arbetstid (4) om det förekommer skämt om sina kollegor och chefer (5) stöld på arbetsplatsen.

    Jag har kommit fram till att det finns en skillnad mellan de olika yrkesgrupperna. Denna skillnad beror främst på vilka möjligheter de anställda har genom sin anställning. Det har visat sig att om de anställda har tillgång till Internet och en fast telefon som betalas av bruket så ökar frekvensen bland de anställda att begå handlingar som kan kopplas till organizational misbehaviour bland de anställda. I denna undersökning så kan även se en skillnad mellan män och kvinnor i handlingar som kan tolkas som organizational misbehaviour.

    Jag har även kommit fram till att det finns klara skillnader mellan de anställda beroende på hur länge man har varit anställd på bruket. Studiens resultat visar bland annat att en bidragande anledning till att anställda ägnar sig åt organizational misbehaviour är att de missnöjda med sitt yrke. I denna studie så kommer jag att arbeta efter fyra frågeställningar dessa är;

    -Förekommer det organizational misbehaviour bland de anställda på bruket?

    -Finns det någon skillnad i organizational misbehaviour bland tjänstemän och

    kollektivanställda bruksarbetare?

    -Finns det skillnader i organizational misbehaviour beroende på hur länge man har varit anställd på bruket?

    -Finns det någon skillnad i organizational misbehaviour mellan de olika könen?

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  • 19.
    Almusaed, Amjad
    et al.
    Jonköping University, Sweden.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Alasadi, Asaad
    University of Basra, Iraq.
    Yitmen, Ibrahim
    Jonköping University, Sweden.
    Al-Samaraee, Sammera
    Basrah University for Oil & Gas, Iraq.
    Assessing the Role and Efficiency of Thermal Insulation by the "BIO-GREEN PANEL" in Enhancing Sustainability in a Built Environment2023In: Sustainability, E-ISSN 2071-1050, Vol. 15, no 13, article id 10418Article in journal (Refereed)
    Abstract [en]

    The pressing concern of climate change and the imperative to mitigate CO2 emissions have significantly influenced the selection of outdoor plant species. Consequently, evaluating CO2's environmental effects on plants has become integral to the decision-making process. Notably, reducing greenhouse gas (GHG) emissions from buildings is significant in tackling the consequences of climate change and addressing energy deficiencies. This article presents a novel approach by introducing plant panels as an integral component in future building designs, epitomizing the next generation of sustainable structures and offering a new and sustainable building solution. The integration of environmentally friendly building materials enhances buildings' indoor environments. Consequently, it becomes crucial to analyze manufacturing processes in order to reduce energy consumption, minimize waste generation, and incorporate green technologies. In this context, experimentation was conducted on six distinct plant species, revealing that the energy-saving potential of different plant types on buildings varies significantly. This finding contributes to the economy's improvement and fosters enhanced health-related and environmental responsibility. The proposed plant panels harmonize various building components and embody a strategic approach to promote health and well-being through bio-innovation. Furthermore, this innovative solution seeks to provide a sustainable alternative by addressing the challenges of unsustainable practices, outdated standards, limited implementation of new technologies, and excessive administrative barriers in the construction industry. The obtained outcomes will provide stakeholders within the building sector with pertinent data concerning performance and durability. Furthermore, these results will enable producers to acquire essential information, facilitating product improvement.

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  • 20.
    Alvarsson, Kristoffer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Ombyggnation av en svetscell: Utformning av inmatningssystemet2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report deals with a project that´s been initiated on the behalf of Morgan Sahlin at Wermland Mechanics AB in Töcksfors and is about to look over and develop a input system for a welding cell. The project is done in the course Degree of Bachelor of Science in Innovation and Design Engineering, MSGC12 at Karlstad University and comprises 22,5 credits.

    Today the company has received a shelf in the production where one of the steps is to apply a reinforcement by welding. At their disposal, they have a welding cell that today is just standing still, taking up space and costs money. The welding cell has previously been semi-automatic but the company now wish to rebuild it so it instead becomes fully automatic. The goal is to develop a concept that suits the company's operations and that at the end of the project gaze upon a functioning fully automatic welding cell.

    The project follows a project model based on the product development process with the phases pilot study, concept generation, concept selection, concept description, layout and detail design. Each phase is supplemented with specially selected design tools. During the process analyzes, observations, interviews and site visits has also been carried out.

    After the pilot study that was based on observations, analysis and gathering of information, a specification took form where the requirements and requests, of what the final product is expected to achieve, were listed. The specification resulted in the project´s first problem: "How should a feed mechanism to an automated welding cell be designed that allow room for shelves and reinforcements, with focus on the user-friendliness?". This problem was the foundation of the upcoming concept generation and the specification became the basis of the choice of concept.

    The process resulted in two concepts that were presented to the client and which corresponded to the established definition of the problem. Both concepts are based on exploiting how the details arrives and means that they are entered directly into the welding cell on the pallets. The concepts differ in how the shelves are stacked on the pallets, one comprises a solution where the shelves are laying down while in the other one they are standing up. The solution suits the company well and can be adapted to most of the operations in their production.

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  • 21.
    Amiri, Karim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Konceptutveckling av en lastcykel: Ett projekt med syfte att utveckla en lastcykel för rullstolsburna2022Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The report deals with a project carried out in connection with the course Examensarbete för höskoleingenjörsexamen i innovationsteknik och design, MSGC36, at Karlstad University. The project was carried out by the student Karim Amiri during the spring semester 2022 and comprises 22.5 credits.

    The aim of the project is to explore and develop a bicycle concept that enables the ability to transport gods, with a focus on people who use assistive devices in everyday life to get around. By getting more people to cycle and accompany the journey, the contact and creation of air pollution can be reduced in the community, leading to increased well-being. The results of the project are limited to work statically environment and not dynamically in practice, where calculations on wheels and how the bicycle behaves in motion are excluded.

    The project builds from the product development process using Double Diamond's phases: Discover, Define, Develop and Deliver. Where the aim is to find the problems and then to find solutions to weave it together into a concept proposal.

    The result of the project is based on a long john cargo bicycle, with a load capacity for one passenger and their wheelchair. With the lack of feasibility study on which manual wheelchairs are popular, it was decided to make a limitation to models Etac Cross 5/6 and Panther U3 with a seat width of 450 mm. The Taxi concept that was selected was justified to be chosen as it is considered that there are no similar ones on the market, that would offer something new and reminiscent of the way of sitting in a car.

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  • 22.
    Anders, Ylén
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Införande SPS Arvika Smide AB: SPS och ISO/TS 169492014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The report is a master thesis carried out in the final part of the Bachelor of Science education in Mechanical Engineering. The work is carried out by Anders Dedorsson Ylén, a student at the Faculty of Health, technology and natural science at the University of Karlstad.

    The work has been performed at Arvika Smide AB, whose mission was to introduce SPS at the pressgroup 5, and examine how well the company is working with ISO/TS 16949.

    The report contains a theoretical part about SPS and ISO standard ISO/TS 16949.

    It also describes how SPS can be used as a method for measuring machine condition and maintenance needs, and how the test's are carried out.

    It describes what has happened in the renovation of the forging press, and the results of measurements made after the renovation work was done.

    An appropriate method is presented to be able to see where the company is in its work with ISO/TS 16949 and suggestions for improved work with ISO/TS is suggested.

    The report shows that the SPS can be used as a guideline in condition-based maintenance of a forging press and how the company can improve its work with ISO/TS 16949.

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    Införande SPS Arvika Smide AB
  • 23.
    Andersson, Andreas
    et al.
    Karlstad University, Faculty of Technology and Science.
    Andersson, Anders
    Karlstad University, Faculty of Technology and Science.
    Kostnadseffektivisering av bärcylinder2007Independent thesis Basic level (professional degree), 15 points / 22,5 hpStudent thesis
    Abstract [en]

    The report intends a thesis work within the machine engineer program at Karlstad University, the employee is Metso Paper Karlstad AB

    Metso Paper produces tissue machines for the paper industry and also performs service and development of these products. Tissue is soft paper which includes hygiene paper and table napkins. Focus in the task is to reduce the cost of the reel drum, which is a detailed component in a tissue machine. The reel drum is a drum which is assembled in the end on the paper machine, in the area where the paper is rolled up on spools. The analyzed items have the dimensions; diameter 900mm with the length 2825 mm and diameter1100 mm with the length 5550mm.

    Initially, the reel drum’s main functions were analyzed, which can be summarized:

    • That with vacuum transport the point (narrow paper chute) from the point swindle groove to the surface between the reel drum and the reel spool

    • To support paper during winding on the reel spool

    • To create a pressure against the reel spool so that a driven torque arises. The torque is required because the reel spool has no own power supply.

    The task was divided in two parts for a simpler procedure,” new structure” and ”improvement and efficiency improvement of existing structure”

    New structure treats calculations concerning the thickness of the shell and choices of alternative materials. Improvement and efficiency concerns how the current structure can be simplified and the production process improved. The result demonstrates that today's structure is unnecessary thick, the shell thickness l can be reduced with maintained function properties. To produce the shell in steel instead of cast iron gives lower purchase cost of materials for reel drums in diameter 900mm, buying to shells at the time almost reduces the material cost with 50%

    In order to make the existing structure and the production process more effective must certain parts of the casting be carried out with higher precision, criteria such as: thickness, roundness and presence of rest products should be taken into consideration. Higher casting precision makes the following machine work easier.

    Finally there exists a big potential to reduce the cost of the reel drum. Important criteria’s that is to be considered are: dimensions, materials and more effective processing.

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  • 24.
    Andersson, Björn
    et al.
    Karlstad University, Faculty of Technology and Science.
    Fransson, Andreas
    Karlstad University, Faculty of Technology and Science.
    Användning av CAD-data vid NC-programmering2007Independent thesis Basic level (professional degree), 15 points / 22,5 hpStudent thesis
    Abstract [en]

    The degree project is performed at Metso Kamfab. The production is aimed on machines everything from handling of fiber to paper pulp. Metso Fiber and Kamfab are using Pro/Engineer for design and blueprint production. The processing department types the NC-programs in notepad on the basis of the blueprints, the CAD-dates that already is there are not used. The aim with the work is to study if Kamfab can use CAM-system for processing and production of programs for their NC-machines. The objective in this project is to make NC-programs that functions in three special machines.

    CAD/CAM forms the link between design and production. In a CAD/CAM-system the geometry is created in CAD and can be used directly in CAM for processing. In CAM CL-data is created and after that translated with a postprocessor to NC-code. The postprocessor is used also as a watch over function.

    Three machines were chosen as experiment items for introducing of CAD/CAM. These are a 7-axis mill, a combined mill/turn and a 3-axis mill. The 7-axis mill and the mill/turn were chosen because they are the most advanced machines. The 3-axis mill was chosen because there was available time in it. Products that were tested were trough, pillar, housing and a part for a toolchanger.

    When processing the trough ”Surface-Mill” was chosen and a lead-angle was set in the parameters. It was most drilling and a little face milling on both the pillar and the housing.

    In order to test programs a postprocessor was borrowed that translated CL-data to Heidenhain code. During the test run errors were detected in the programs. This depends on that the postprocessor not where customized for the machine. A postprocessor developed by ourselves was also tested, this one didn’t work because the machine's NC-system couldn’t read ISO standard code.

    A study visit was done at Structo in Kristinehamn where EdgeCAM is used for NC-processing. It works well and it allows quicker and safer programming.

    Pro/Engineer is powerful and has a lot of possible adjustments. This makes it complex and takes time to learn. To use Pro/Engineer´s CAM-part it is necessary to have basic knowledge about the CAD-part. Depending on this many companies uses for example EdgeCAM that almost is a pure CAM-system.

    The processing of the three components functioned well in Pro/Engineer, we could process the components after demands. The problem was to get working programs. An advantage with using CAM is that you can simulate toolpaths. Through this you can see if the tool collides and it also makes it possible to optimize toolpaths. Today, it is a lot of waiting time in the milling machine FPT34 because programs are not completed. This waiting time would be reduced or even eliminated with the aid of CAM.

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  • 25.
    Andersson, Camilla
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Johansson, Maria
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Att vara eller inte vara: styrs uttaget av föräldraledighet av föreställningar eller faktiska förhållanden?2006Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    The purpose of this survey is to investigate how well parents ideas and conceptions concerning parental leave, matches factual circumstances, or if there is a difference? More specifically it has been investigated if it is the common conceptions concerning the obstacles for the male parental leave which is in control, or if it is the actual circumstances which control the parental leave? The survey is based on a quantitative empiric where the collection of data has been done through a selection of availability with a questionnaire as the measuring instrument.

    In order to find the answer to the question at hand, theory in the field of parental leave and gender has been studied. The theory section contains a presentation of the parental leave discourse with its four obstacles; economy, workplace, the woman and the gender roles. The section is the base of our understanding and has also been the framework from which the questions for the survey have been constructed.

    The results from the empirical survey have been analyzed together with relevant literature to give an answer to the question at hand. From this it can be read that the distribution of the days of the parental leave is highly affected by the conceptions and ideas males face concerning parental leave. The results also clearly show that the obstacles partially are not rooted in reality. In the survey it also surfaced that those responding had insufficient knowledge concerning the parental insurance which we believe has aided the conceptions and ideas to the influence and degree they have had. The authors hence believe that the information to the parents should improve and that researches in the field should find strategies in order to better inform the public of their knowledge.

    Keywords: Parental insurance, parental leave, gender system, discourse and obstacle

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  • 26.
    Andersson, Christian
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Förbättring av utnyttjandegrad hos stansmaskin2008Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Bakgrunden till examensarbetet är att det finns ett behov av att höja utnyttjandegraden i stans- och lasermaskiner hos Lars Höglund AB. Anledningen till att utnyttjandegraden behöver höjas är att företaget vill bli mera lönsamt och mera konkurrenskraftigt.

    Uppgiften har varit att mäta utnyttjandegraden, göra en probleminventering och ta fram förslag på åtgärder som kan lösa de problem som kom fram i probleminventeringen.

    Vid probleminventeringen visade det sig att det går att höja utnyttjandegraden genom att bl.a. göra en ställtidsreducering, skapa ordning och reda, samt att förebygga flaskhalsar.

    5S är en metod som har använts för att ta fram förbättringsåtgärderna. Genom att följa denna metod, samt att göra några nya investeringar i företaget, ser det ut som att målet i detta arbete ska kunna uppnås.

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  • 27.
    Andersson, David
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Förstudie för förbättrad problemlösning och förbättringsarbetet hos Mastec Stålvall2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 28. Andersson, Elliot
    et al.
    Guldbrandsson, Andreas
    Värdeflödesanalys av process förframtagning av PM-pulver2023Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
  • 29. Andersson, Erik
    Hydrostatisk drivlina: För tunga lastfordon2012Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
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    Hydrostatisk drivlina
  • 30.
    Andersson, Erika
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    De fem enkla maskinernas integrerande i den fria leken inom förskolans arena: En studie baserad på barns undersökande av enkel teknik i den fria leken.2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study is to demonstrate how children apply simple technology in preschool through “The Big Five”. Observations and "Interview on the move" are the method choices that answer the purpose and questions of the study. Observations and interviews have been conducted in the preschool outdoor environment during a morning and are based on the children's free play where the aim is to start from the children's perspective and reflections. The situations that have been chosen for the study are based on the children's curiosity and demonstrated interests. The result of the study shows that two of “The Big Five” are applied by the children in the preschool outdoor environment and free play. This is demonstrated by their use of the leaning plane and the wheel from “The Big Five”. It shows by their use of tools such as exploration, part of the game and through concepts. This is done through a sociocultural perspective where different factors influence children's learning.

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    fulltext
  • 31.
    Andersson, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Numerisk modellering av tvåfasströmning och syretransport i bubbelkolumner: Metodutveckling för att förutsäga syretransportshastigheten i rent vatten och surfaktantlösningar2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In connection with a global population increase and economic development, the consumption of freshwater and the production of wastewater is increasing. Wastewater needs to be treated to convert it into an effluent that can be safely released without negative environmental impacts. One of the most common wastewater treatment technologies is aerobic biological treatment, where bottom aeration – the procedure of pumping air through submerged diffusers which generate bubbles to oxygenate the wastewater – is the most energy demanding process. The oxygen transfer rate from air bubbles to wastewater is negatively affected by the presence of surfactants, a ubiquitous contaminant in both municipal and industrial wastewaters.

    To assure a sufficient treatment efficiency as energy efficiently as possible, an understanding of the oxygen transfer process in bottom aeration systems is necessary, and for designing of new systems and calibration of existing ones, tools facilitating prediction of the oxygen transfer rate are required. The purpose of this study was to develop a numerical tool to estimate the oxygen transfer rate for lab-scale bottom aeration systems and to contribute to the basis of knowledge regarding oxygenation of surfactant solutions. The primary goal of the study was to develop a CFD-model coupled with a mass transfer model to predict the oxygen transfer rate in bubble columns containing clean water, and the secondary goal was to apply the model to water-based solutions of the surfactant lauric acid (DDA) and identify options for further development of the model to make it applicable for surfactant solution systems.

    The model was developed with COMSOL Multiphysics 5.5 and included a two-dimensional axisymmetric geometry, URANS-equations and standard k-ε to for turbulence modelling, and an Euler-Euler mixture model for the two-phase flow. For oxygen transfer modelling the two-film theory, Higbies penetration theory and the advection-diffusion equation were used. Bubble diameter is an important parameter in several of the equations used and the Sauter Mean Diameter was calculated to represent the average bubble diameter, based on available experimental data for different combinations of air flow rate and DDA-concentration.

    Results of the simulations regarding the oxygen transfer rate in clean water fit well with experimental data at lower air flow rates, and the difference for the volumetric mass transfer coefficient was 0,7 % and 3,3 % for the air flow rates 0,1 l/min and 0,2 l/min, respectively. For the air flow rate 0,3 l/min the difference was 14 %; because of the flow regime being more heterogenous at higher air flow rates, the model tends to overestimate the oxygen transfer rate. In surfactant solutions the model overestimated the oxygen transfer rate due to surfactant adsorption on the bubble-water interface – and the consequent decrease of the mass transfer coefficient – not being modelled. Either a correction factor for the mass transfer coefficient – based on the difference between simulated results and experimental data – needs to be calculated and applied, or the underlying theories describing the oxygen transfer require revision. Potentially the mass transfer and interfacial adsorption of surfactants could be modelled to emulate reality more accurately.

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  • 32.
    Andersson, Gustav
    -.
    Handling-Force Software: Calculation software for tailgate and bonnet in concept stages2019Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract

    This report focuses on the creation of a software to calculate handling forces of bonnet and tailgate. The handling force is the force required by a user to open or close a tailgate. It is a bachelor thesis conducted for Karlstad’s university. The work is conducted at CEVT in Gothenburg, the software will be used to improve workflow in early design phases.

    The resulting software from this project is easy to use and shows good resemblance to the reference values, which is old calculations done by a manufacturer. Comparing to manufacturer calculation the software shows only small deviations in results. The software is deemed to be an asset in the development work at CEVT.

    The software is also easy to use and have been tested by employees, whom could operate the software easily without instructions. It is based on regular equilibrium equations and the software structure is logical and easy to follow, to make it simple to maintain and develop the software if the need would arise.

    The finished software calculates single pivot hinges and four bar mechanism-based hinges equipped with gas springs. It also has the possibility to work with tailgate and bonnet simultaneously to keep one project in one file.

    The work has focused on, creating the software, user interfaces and kinematics/kinetics of different types of hinges, with support from both literature and reports. This led to a software built in Microsoft Excel, which was chosen due to its standard features for graphical display of data. Building the software in Excel also makes it accessible to all employees who wishes to use it.

    The conclusion is that the software could in extension lead to higher quality on finished products by allowing more tested configurations and continuous changes during the design process.

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  • 33.
    Andersson, Gustav
    Karlstad University.
    Modifiering av robotcell till nytt  format på lösullsbalar2020Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
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    fulltext
  • 34.
    Andersson, Jim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Manufacturing of Welded Rings: Evaluation of Post-Weld Operations2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Pipe and ring blanks can be produced in several different ways. Today's focus on environmental effects motivates companies to develop processes that are as efficient as possible in their production. Ringsvets AB is a company that produces pipe and ring blanks from a flat stock by rolling and welding the piece to make it stay in its desired form. The direct benefit of the method is the minimizing of material loss, and it has thereby both environmental and economical advantages. The downside of the method is that the processes involved changes the mechanical behavior of the ring, locally around the weld zone. The focus of this master thesis is the processes and how they affect the material, both microstructure and behavior. The processes involved are; rolling, welding, shaping, brushing, forging, heat treatment, and calibration.

    The purpose of this work was to elevate the knowledge and understanding of the processes at Ringsvets. The goals were to give a theoretical description of them along with practical test results and explanations of how and why they function in reality.

    A literature study has been conducted which provided a theoretical basis on how the material reacts on certain processes. Practical examination of samples from current production has been done to get evidence of how well the processes are used, and how well they function, in today's production. Lastly, the main focus of the thesis, an evaluation has been made; do theory and practice correlate, and should anything be changed to correlate better?

    The results showed that the first operations do not alter the material behavior to an unacceptable extent. Forging, on the other hand, gives the material a very high hardness in the weld zone, and that needs to be corrected. The following heat treatment should compensate for that in a perfect world, but does not in reality. The finished ring shows good properties in general but with places where the heat treatment has failed to correct the uneven behavior induced by earlier operations.

    The heat treatment requires some adjustments before it functions as intended. Some grainshas not been recrystallized which makes them very hard and non-ductile. Future tests using a higher temperature or a longer heat treatment time would reveal the best way to adjust the heat treatment to obtain the desired properties. Other changes in the processes could also be benecial. Interesting things to try and change would, for example, be the degree of deformation in the forging, which affects the recrystallization temperature.

    Notes should be taken that this examination is done on just one sample of just one size. Analyses of different samples of different sizes should be done to ensure of the accuracy of the examination.

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    Arkivfil
  • 35.
    Andersson, Johannes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Förbättring av Camcoil: Integrering av stöd samt bandnyp2013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract

    The assignment were assigned by Camatec Industriteknik AB. Camatec is a Karlstadlocated consulting company, they make everything from pilot studies to complete projects in mechanical design and calculation. They even have their own patented product, Camcoil. It is a winder for steel strips and is used for example with hardening of the steel strip. The assignment has been to solve the problems encountered by some customers within this product. The product which is relatively simple consists of a mantle which can vary in diameter by means of hydraulic cylinders The problem was that it had concurred indentations on the striped steel next to the Camcoil. This destroys the further handling of the coil. The goal has been to develop three kinds of solutions that take into account different customer requirements. These solutions have been divided into price ranges, thus low-cost, mid-cost, and high-cost. The high-cost solution has been a combination of the mid-cost-solution and a bandgrip. One wish was to simplify the existing bandgrip.

    The functional requirements those are set depending on the customer:

    • Must be able to prevent sagging, then some form of support should be available to the band at reeling.

    • Not allowed to weld in the mantle beneath the welded ears.

    • Must be able to take a band-pull at max 1 ton.

    • The space at the clearance on the reel should be free at the use of lifting hook (midcost, high-cost)

    • Steel strip with thickness 0.2-1 mm is to be pinched to the reel (High-cost).

    • A stop for the band at pinching must exist (high-cost).

    The non-functional requirements that have applied for all price ranges:

    • Develop the simplest solution as possible.

    • Standard components recommend being used to reduce costs.

    • The solution should be user friendly and easy to maintain.

    The major problem has been the lack of space in the reel with the requirements of midcost solution. Due to a lifting hook to be used it has been very difficult to come up with a mechanism that would work as a support. A comprehensive concept generation has been done with a number of different concepts for each price ranges solution. The concepts have been evaluated and compared and with the help of elimination- and decision matrix has a concept selection for each price range been developed. The result for the low-cost solution is a rolled sheet metal that is overstrung on the outside of the mantle, this means when the mantle will collapse the rolled sheet metal will follow along. Mid-cost solution resulted in a mechanical lid uses mantle movement with the help of parallel rods wander vertically down and account the space for the lifting hook. A simplification of the bandgrip were made with boomerang stays, this gave more space and fewer parts. The combination of the mid-cost solution and the simplified bandgrip were the high-cost solution.

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  • 36.
    Andersson, Kimberly
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Parametriska symboler för utrustningsritningar inom processindustrin2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    On behalf of CWR Engineering AB a development project has taken place. The goal of the project was to determine whether or not it is possible to create an application which can make working process of the mechanical engineer, in the process industry, run with higher quality assurance and efficiency whilst creating equipment drawings. The development process within process industry strives towards being cross- functional. All design is based on the Piping and Instrumentation Diagram (P&ID), where the process, for example a chemical plant, described in 2D where the piping, equipment and instruments are specified to type, but not position. The equipment is then described in detail in a 2D drawing. The 2D drawing in turn is the basis for the equipment when creating it in 3D. Finally, the 3D model is placed into the factory layout in a 3D environment. The factory layout correspond to the design determined in the P&ID.

    An equipment drawing differs from a standard mechanical drawing in the sense that it has no standard for its views, such as a mechanical drawing can be designed by either a European or an American standard. The equipment drawing must however still meet the requirements of defining all components described within the P&ID, which can be done in some different ways. The format for these drawings creates possibilities for error, which the developed application is to prevent. In this project, the study was limited to tanks with its nozzles.

    The project has resulted in a layout concept for an application in the engineer's computer environment which creates a built-in error-proofing in the working process. It makes the process more efficient. The concept has been developed through analyzing the working process used today and the software the engineer uses in his work. A flow for the technical information have been identified and based on these data, the concept has been developed.

    The layout concept consists of three parts. First, a drawing file management form which creates, deletes, revises and correlate the status of all equipment drawings to the data in P&ID. All data from these diagrams are stored in a Microsoft SQL Server database. Using Microsoft Visual Studio this data can be used to create, manage and control the equipment drawings in a semi-automated way. The drawings are created in 2D CAD software SmartSketch. The SmartSketch user is currently using symbols, which are pre-drawn static components which the user can place on the drawing and then scale to preferred size. These symbols are available in various executions depending on the nozzle to be placed. The second part of the concept consists of making these symbols dynamic and driven parametrically through a dimensions database. Information about the standpipe size, dimensions standard, pressure rating and end preparation comes from the P&ID data, which then retrieves information about parametric dimensions in a database. The symbol automatically receives correct dimensions and can be placed on the tank. The amount of symbols can therefore be reduced since the symbol's graphic changes parametrically. If any variable of the nozzle is be changed, the symbol will automatically be updated. The user can also manually change variables such as size and pressure class, even before the changes take place in the P&ID, as a part of cross- functionality. The third main functionality of the concept is the examination of the drawing data pertaining to the positioning and view conformity of the nozzles. The examination result is to be reported in a PDF file and in a dialog window.

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  • 37.
    Andersson, Lukas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Self-locking Brake used in Reversible Sailboat Winches: Development of a self-locking braking system that will be used to allow sailboat winches to reverse2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sailboat winches are used to help sailors manipulate the control lines that control the position and shape of the sails. Unlike most winches sailboat winches usually only have the ability to winch in the rope, but not to reverse. To reverse the line a sailor needs to manually manipulate it, this is both inconvenient and can also be a safety hazard.

    This master’s thesis will focus on the development of a self-locking braking system that will be used to allow a sailboat winch to reverse. The goal of the thesis is to design a braking system that works with a modified version of the E40i winch produced by Seldén.

    The braking system that was developed during this thesis is made up of two main parts, a one-way mechanism and a brake. The type of one-way mechanism that was chosen was an overrunning roller clutch. For the brake a wet disk brake was chosen with an outer diameter of 50mm and an inner diameter of 28.8mm.

    A 3D model of the braking system has been generated and materials have been selected so that the system is ready for prototyping and physical testing.

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  • 38.
    Andersson, Malin
    et al.
    Karlstad University, Division for Business and Economics.
    Hedlund, Emma
    Karlstad University, Division for Business and Economics.
    Ledarskap: En jämförande studie mellan personalchefer och andra chefers ledarskap2006Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Sammanfattning

    Denna C-uppsats i arbetsvetenskap är en kvalitativ studie och baserad på teorier om ledarskap. Syftet med uppsatsen är att undersöka likheter och olikheter mellan personalchefer och andra typer av chefers ledarskap.

    Inledningsvis presenteras en historisk bakgrund av ledarskapets förändring. Sedan följer grundläggande ledarskapsteorier samt teorier om kommunikation, makt, motivation och genusperspektiv. Dessa teorier är en viktig grund för analys- och resultatavsnittet i uppsatsen. Utifrån dessa teorier utformas en intervjuguide. Datainsamlingen sker genom intervjuer. Totalt genomförs sammanlagt sex intervjuer. Respondenterna är en områdeschef, en affärsområdeschef, en kontorschef samt tre personalchefer. Intervjuerna transkriberas och vi undersöker likheter och olikheter gällande ledarskap mellan personalchefer och övriga chefer. Vi får fram följande teman: synen på ledarskap, att vara ledare, utveckling av ledarskapet, ledarstilar, kommunikation, motivation, makt och ledarskap ur ett genusperspektiv. En sammanfattande diskussion av analys och resultat görs. Uppsatsens slutsats är att personalcheferna, i större utsträckning än de övriga cheferna, inte bara automatiskt bedriver ett chefskap utan också ett ledarskap.

    Nyckelord: ledarskap, likheter, olikheter, kommunikation, motivation,

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  • 39.
    Andersson, Martin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Torkning integrerat med kraftvärmeverk: Påverkan av energibalanser i torksystem vid integrering till kraftvärmeverk2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I Sveg finns ett pneumatiskt torksystem. Systemet har sedan 1989 torkat torv till briketter men har på senare tid torkat både trä och torv för produktion av bränsle i form av pellets och briketter. Idag består anläggningen av två symmetriska torklinjer. I torklinjerna används en värmepumpkrets för återvinning av råvaruånga. I värmepumpkretsen används en kompressor driven av inköpt elenergi. Planerna är att integrera en av linjernas nuvarande torkprocess till ett kraftvärmeverk genom installation av ångpanna med bränslet torv och således producera el istället för att köpa el. Integrationen till kraftvärmeverket ger torklinjens värmepumpkrets ett nytt utseende. Kompressorn tas bort i utvald torklinje och ersätts av två lågtrycksturbiner. Det nya utseendet av värmepumpkretsen kommer innebära ett samspel mellan torkning och kraftvärmeverk. I värmepumpkretsen används olika ångflöden beroende av vilket råvarumaterial som torkas. Därför beräknades och användes olika ångflöden beroende av olika fukthalter och inmatningar i torksystemet för att se hur el- och fjärrvärmeproduktionen i kraftvärmeverket påverkades. Samtidigt jämfördes nuvarande torksystem med torksystem integrerat med kraftvärmeverk ur ett energiperspektiv genom förändring av el, fjärrvärmeproduktion och biobränsle.

    Fjärrvärmeproduktionen i kraftvärmeverket ökade vid ångflödena 31,0 ton/h och 24,0 ton/h ”till kompressor” men på grund av större beräkningsosäkerhet bortsågs dessa. Detta gav en varierad sammanlagd fjärrvärmeproduktion av systemen mellan 23,0-23,8 MW respektive 22,0-22,5 MW vid torkning av torv respektive trä (bortseende av torvscenario 1 vid fukthalten 65 %). En fjärrvärmeproduktion i den storleken, jämfört med Svegs fjärrvärmebehov, kan sägas vara för stort. En stor problematik blir därför vad all spillvärme ska användas till, framförallt på sommaren.

    Vid integrering till kraftvärmeverk minskade ”bränsle” medan ”fjärrvärme” och ”el” ökade. Beroende av vilket råvarumaterial som torkades gav en integrering ett större resultat för ”el” men mindre ”fjärrvärme” och ”bränsle” vid torkning av trä. Därför rekommenderas torkning av trä eftersom större resultat av ”el” minskar inköpt elenergi samt mindre ”fjärrvärme” resulterar till mindre spillvärme.

    Vid beräkningarna användes Simulink, ett verktyg för grafisk lösning av differentialekvationer, som ingår i programvaran MATLAB från Mathworks. I Simulink formerades olika ekvationer i statiska beräkningsmodeller för beräkning av energibalanserna i nuvarande torksystem och torksystem integrerat med kraftvärmeverk. Energibalanserna i nuvarande torksystem undersökte svårplacerade effektförluster samt genom olika energibalanskontroller kontrollerade och bedömde trovärdigheten i beräkningsmodellen. Resultaten för energibalanskontrollerna kallades ”beräkningsosäkerhet” vilket var en av flera parametrar som framlade bevis för ett variabelberoende, känsligt, komplext och svårtydande torksystem där övriga effektförluster var svåra att placera. Ett mer korrekt resultat av nuvarande system kan därför möjligtvis uppnås vid användande av en dynamisk istället för statisk modell samt användande enbart av mätdata istället för dimensionerande värden och således göra effektförlusterna lättare att placera.

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  • 40.
    Andersson, Mattias
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Kylskåpsinredning: Praktiska funktioner2008Independent thesis Basic level (professional degree), 15 points / 22,5 hpStudent thesis
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  • 41.
    Andersson, Michael
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utveckling av markinfästning för bruk i låghållfast jord2023Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    To anchor various structures in the ground, there are currently only a few options available. The most common and readily accessible methods for ground anchoring are either pouring concrete foundations or installing ground screw. While these methods have their advantages and disadvantages, the disadvantages make them unsuitable for quick and easy installation by individual and inexperienced homeowners. The goal was to develop a concept that can complement existing methods, with a focus on securing anchoring in low-strength soil and in soil with higher strength but at shallow depths. Emphasis was placed on user-friendly installation and cost-effective manufacturing. The result is an anchoring system comprised of two nestled brackets, through which several piles are driven into the ground. The pile angle has been determined with calculations on the shear strengths of typical Swedish soils. 

    This work has been carried out as a bachelor’s thesis at Karlstad University, commissioned by the company Invencon AB.

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  • 42.
    Andersson Nykvist, Atle
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    New design and construction of hightemperature tribology testingequipment: in the context of hard coatings2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are two main goals of this thesis. Firstly, to improve and develop an existing hot weartester at Karlstad University so that it may test more samples of different sizes. Secondly, totest previously impossible samples and investigate their tribological properties and measurethe coefficient of friction with high reproducibility. The development work on the tribometer wasdone by a prestudy including; Investigating the hot wear tester, idea generation in CAD andcollecting information from the creator and prior users of it. After a few rounds of conceptgeneration and discussion with the supervisor and workshop staff, a new sample holder withdifferent sample adapters was created. Five tests of four different materials were conductedand their friction was measured. The new sample holder was able to solve the mainconcerns with the old design and showed great promise in producing reproducible results,better than any previous versions. The friction of the different TiAlN samples, at roomtemperature, seemed to indicate that there is a certain amount of Al% that maximizes frictionand that there is no simple linear relationship between Al% and coefficient of friction. Finallyit can be concluded that the initial goals of the thesis have been met, and that a newscientific instrument has been created to aid in the further understanding of tribology. 

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  • 43.
    Andersson, Patrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Standardization in additivemanufacturing: Recommended parameters and fixture solutions for hybrid printing2023Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This study analyses and examines the hybrid printing process at Uddeholms AB in Hagfors.The objective of this study is to present recommended parameters to achieve optimal printingresults in a newly developed steel as well as a steel powder material designed for additivemanufacturing.The study showed that the best results occurred when printing on metal in a delivery state,with a thin layer thickness and double exposure. This resulted in full density in the fusion zoneand a gradient hardness change compared to a linear hardness change which was achievedwhen using single exposure. This leads to a lower chance of crack initiation due to internalstresses in the material.Additionally, a fixture system is presented that can fixate a variety of geometriessimultaneously. The use of this fixture system leads to a reduction in lead time by up toapproximately 85% comparing to the fixture solution in use today. Another benefit is theincreased economic sustainability since the operator does not need bespoke fixturing solutionsfor specific jobs.To achieve optimal properties of the printed detail, the parameters presented in this studyshould be used in conjunction with the fixture system.

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  • 44.
    Andersson, Rasmus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    CAE Tool for Evaluation of Park Lock Mechanism in a DCT Transmission2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A park lock mechanism is a device that is fitted to an automatic transmission on a vehicle. The mechanism lock up the transmission so that no rolling of the vehicle can be done when the vehicle is put in the park position.

    The aim of this thesis is to develop a method in order the evaluate designs on a Park Lock Mechanism (PLM) that can be found in a dual clutch transmission (DCT).

    A Computer Aided Engineering (CAE) tool to calculate the output that is required for an evaluation of a park lock mechanism design will be created. The CAE tool shall calculate static, dynamic, and snap torque on a ratchet wheel in a gradient, with or without a trailer, also the minimum and maximum coefficient of friction between the pawl and cone, pull out force, the maximum amount of rollback, torque needed from the return spring, preload force from actuator spring, and engagement speed.

    The CAE tool created uses an Excel Visual Basics for Applications (VBA) workbook for all calculations. The tool allows the user to choose different vehicles with the required specification to evaluate the values for that PLM.

    The CAE tool will save time and cost if lots of different PLM’s are going to be designed. The CAE tool has potential for future work when more calculations can be added that can be in use for the evaluation the PLM.

    The CAE tool developed by the master thesis student calculates all the required values for evaluation of a PLM design, executed in a fast, efficient, and easy to use program. 

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  • 45.
    Andersson, Tim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Computer Modeling of Thermodynamic Flows in Reactors for Activated Carbon Production2014Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
    Abstract [en]

    There's a big demand for activated carbon in Ghana, it's used for the country's mining industry as well as in a multitude of other applications. Currently all activated carbon is imported despite the fact that the country has a large supply of agricultural waste that could be used for its production. This study focuses on activated carbon production from oil palm kernel shells from the nations palm oil industry.

    Earlier research points to a set of specific conditions needed for the production. The pyrolysis process produces biochar from the biomass and the process is set to take place for 2 h at 600  °C after a initial heating of 10 °C/min. The activation process then produces the activated carbon from the biochar and is set to take place for 2 h at 850 °C with a heating rate of 11.6 °C/min.

    Two reactors are designed to meet the desired conditions. The reactors are both set up to use secondary gases from diesel burners to heat the biomass. The heating is accomplished by leading the hot gases in an enclosure around a rotating steel drum that holds the biomass. To improve the ability to control the temperature profile in the biomass two outlet pipes are set up on top of the reactor, one above the biomass inlet and one above the biomass outlet. By controlling how much gas that flows to each outlet both the heating rate and the stability of the temperature profile can be controlled. The secondary gas inlet is set up facing downwards at the transition between the heating zone (area of initial heating) and the maintaining zone (area of constant temperature).

    The two reactors are modeled the physics simulation software COMSOL Multiphysics. Reference operating parameters are established and these parameters, as well as parts of the design, are then changed to evaluate how the temperature profile in the biomass and biochar can be controlled. A goal area was set up for the profile in the biomass where it was required to maintain a temperature of between 571.5 and 628.5 °C after the initial heating to be seen as acceptable. Similarly a goal area was set for the biochar between 809 °C and 891 °C after the initial heating.

    It's found from the simulations that the initial design of the reactors work well and can be used to produce the desired temperature profiles in the biomass and biochar. Furthermore it's concluded that the initial design for the pyrolysis reactor can be improved by having the gas outlet pipe situated by the biomass inlet face downwards instead of upwards. The redesign improves the overall efficiency of the reactor by increasing the heating rate and maintained temperature.

    The evaluation of the operating parameters led to the conclusion that the secondary gas inlet temperature effects the temperature profile to a greater extent than the gas mass flow in both reactors thereby making them more energy efficient. The increase in efficiency comes with a drawback of more unstable temperature profile. If the temperature profile becomes too unstable it will include temperatures that are too high or too low to be seen as acceptable.

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  • 46.
    Andersson, Victor
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Flödesanalys av roterande ventil i ångmotor2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report is a bachelor thesis at Karlstad University in collaboration with Invencon AB and Ranotor AB. The goal was to analyze a rotating valve leading water vapor through an inlet and five outlets. The quantifiable results that were addressed in this project are the mass flow through the outlets and the forces affecting the valve and its shaft (primarily radial forces). The tools used for this project are PTC Creo and ANSA for modelling and mesh as well as ANSYS-CFX and Matlab for computational help. The results show that the specified rotational speed of 4600 rpm doesn’t work for this model. The rotational speed was chosen because of an interest in this specific operating condition. A 3 mm radial gap between the rotating valve and the valve housing proved to cause a leakage in the form of pressure loss inside the valve. The boundary conditions that were laid out for this project are not valid for this operating condition. Since the difference in pressure is large (100 down to 1 bar) the flow is choked. A large difference in pressure also makes it important to adjust the total area of the outlets, since the pressure drop affects the density of the vapor. The forces on the rotating valve that were calculated (using ANSYS-CFX) create a foundation for choosing bearings for the valve. If the construction is modified, and/or the rotating valve will operate at a different rotational speed these forces will be subject to change.

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  • 47.
    Andreasson, Frida
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Working Life Science.
    Johansson, Martin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Working Life Science.
    Trivsel på arbetsplatsen: En kvalitativ studie om lärares trivsel på arbetsplatsen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 48.
    Andrée, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Nya metoder för vibrationsmätning på vindkraftverk2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This project has revolved around finding better ways of overseeing vibrations of the gearbox at a wind power station. The gearbox has been a huge problem at the stations located at Gässlingen and the sooner the warning of an incoming breakdown is at hand the more money you can save from preparations. The work has been carried out together with Askalon AB in cooperation with consults from ÅF. Askalon is a company with a department focused on overseeing vibrations and it is in collaboration with that department the work has been carried out.

     

    During this work, new positions for the sensors and new methods of gathering and analyzing data have been worked out. This was then implemented at a wind power station to be tried out on site. The measurement has been overseen online via remote control and the results have been analyzed in a program called AMS Suite: Machinery Health Manager.

     

    The new type of measurement shows that some kind of damage has been done to a specific part of the gearbox and that there is a risk it might escalate. However the measurement used today has not yet alarmed and therefor the conclusion made from this is that the project has been successful. Therefor it is time to refresh the overseeing of vibrations.

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  • 49.
    Andrésen, Albin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Att förutsäga temperatur, utgående fukthalt och tryckfall i en pneumatisk transporttork2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Användningen av pellets har ökat kraftigt de senaste åren och har blivit ett viktigt verktyg för att minska miljöpåverkan. I energibranschen är viktigt utreda möjligheten att effektivisera tillverkningsprocessen för att ligga i framkant av utvecklingen och göra bränslet till ett attraktivt val för konsumenterna. En stor del av pelletstillverkarnas utgifter går till att torka det råmaterial som pellets består av. Torkning och transport av material är två energikrävande processer som är nödvändiga i många industrier och kan ibland innebära stora utgifter såväl kostnadsmässigt som miljömässigt. Pneumatisk transporttorkning är ett sätt att kombinera torkning och transport av material och tekniken kan vara lämplig att använda vid pelletstillverkning. På Karlstads Universitet finns en pneumatisk transporttork vars syfte är att forska och utveckla torkning av råmaterial.I den här studien byggdes en modell för att hjälpa användaren att förutse vilket tryckfall och utgående fukthalt som kan förväntas vid torkning av sågspån. Modellen kan användas som ett hjälpmedel vid planering av försök i Karlstads Universitets pneumatiska transporttork.Modellen byggdes i beräkningsverktyget Excel. Dess resultat jämfördes med testserier genomförda i Karlstads Universitets pneumatiska transporttork. Totalt genomfördes trettiotre olika testserier då tryckfall och utgående fukthalt jämfördes. Testserierna skiljde sig ifrån varandra i fråga om massflödet luft, material och ingående lufttemperatur.Vid lägre lufttemperaturer förutsåg modellen en högre utgående fukthalt än vad som kunde uppmätas. När den ingående lufttemperaturen var 120 °C förutsågs ibland rätt, ibland högre och ibland lägre fukthalt i jämförelse med testserierna. Tryckfallet kunde med god noggrannhet förutsägas då lufthastigheten var låg. Då hastigheten var högre var differensen mellan mätdata och modellen större.Känslighetsanalysen visade att en möjlig förklaring till att modellen i vissa fall förutsåg en hög fukthalt kan vara att vissa materialegenskaper var felaktigt antagna. Störst påverkan hade antagandena angående partiklarnas densitet och antalet partiklar som flödar genom systemet per sekund. Det simulerade tryckfallet påverkades inte av ovan nämnda antaganden.Modellen har stor utvecklingspotential men vidare studier rekommenderas för att skapa en bättre förståelse för såväl den pneumatiska transporttorken som modellen. Studierna bör främst riktas mot att bestämma partikelegenskaper och att kontrollera hur väl tryckfallet överensstämmer men mätdata i hela torken. Om det genomförs finns goda möjligheter att modellen kan bli användbar för användare av Karlstads Universitets pneumatiska tork.

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    Andrésen Albin, pneumatisk torkning, tryckfall, fukthalt
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  • 50.
    Ankartoft, Robin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utveckling av kaffemaskin för event2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report covers a product development project conducted by Robin Ankartoft as Bachelor of Science thesis for the innovation & design engineer program at Karlstad University. 

    The assignment was provided by the company 3TEMP AB, Arvika. The company has requested a concept proposal of a coffee machine for events. The coffee machine has to be able to serve coffee fast and during long periods of time, to the visitors of different events. The product also has to be able to be used in different environments, as for example in events like skiing contests, festivals, hockey games or weddings. In the assignment from the company 3TEMP, a powerful, flexible and user-friendly product was sought, that also had good ergonomic qualities. 

    The objective of the project has been to develop a product concept of a coffee machine for events, using the design methodology and an engineering approach. The concept shall meet the needs, requirements and expectations of the user and of the company. It should also have a design that because of its functionality and idiom stands out among today’s products.  

    The outcome of the project was a concept proposal of a coffee machine for events. The concept is based on knowledge of the user to make the product user-friendly by having good ergonomics and being easy to understand as well as use. The concept aligns with the vision of 3TEMP and is, thanks to its design and functionality, considered to stand out among today’s products.

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